Touch sensing circuit, driving chip, display device and signal processing method

Abstract

Embodiments of the present application provide a touch sensing circuit, a driving chip, a display device and a signal processing method. The touch sensing circuit comprises a plurality of charge conversion units and a plurality of signal gating units; a first input end and a second input end of each signal gating unit are electrically connected to an output end of one charge conversion unit respectively; each signal gating unit is configured to receive two first voltage signals, and if one first voltage signal is greater than the other first voltage signal, the first voltage signal with a greater voltage signal is taken as a to-be-detected signal and output from an output end of the signal gating unit; the to-be-detected signal is used to determine whether a touch sensing block corresponding to the to-be-detected signal exists. The touch sensing circuit of the embodiments of the present application can output an effective signal to be detected, so that only the effective to-be-detected signal needs to be detected, effective detection of touch is realized, the detection time is shortened, and unnecessary power consumption loss is reduced.

Description

Technical Field

[0001] This application relates to the field of touch technology, and more specifically, to a touch sensing circuit, a driver chip, a display device, and a signal processing method. Background Technology

[0002] As the size of display panels increases, the number of touch sensing blocks (TX blocks) in the panels also increases, requiring a greater number of analog front-end circuits (AFEs).

[0003] During touch detection, an excessive amount of analog signal feedback from the AFE (Analog-to-Digital Converter) increases the number of signals that the ADC (Analog-to-Digital Converter) and MCU (Microcontroller Unit) need to process. Furthermore, since there is typically only one touch TX (transfer) point at a given time, only one actual, valid touch signal needs to be detected; the other analog signals fed back by the AFE are invalid.

[0004] Therefore, in existing technologies, detecting all touch signals results in many invalid detections, leading to longer detection times and higher power consumption. Summary of the Invention

[0005] This application addresses the shortcomings of existing methods by proposing a touch sensing circuit, a driver chip, a display device, and a signal processing method to solve the technical problems of long detection time and high power consumption caused by many invalid detections when detecting all touch signals in the prior art.

[0006] In a first aspect, embodiments of this application provide a touch sensing circuit, including: a plurality of charge conversion units and a plurality of signal gating units;

[0007] The first input terminal and the second input terminal of each charge conversion unit are used to receive the charge conversion signal and the excitation voltage signal, respectively. The output terminal of the charge conversion unit is used to output the first voltage signal. The charge conversion signal is obtained based on the charge change generated by the sensing signal of the touch sensing block corresponding to the charge conversion unit. The first voltage signal is obtained by converting the charge conversion signal based on the excitation voltage signal.

[0008] The first and second input terminals of each signal gating unit are electrically connected to the output terminal of a charge conversion unit, respectively.

[0009] Each signal gating unit is used to receive two first voltage signals. If one first voltage signal is greater than the other, the first voltage signal with the larger voltage signal is used as the signal to be detected and output from the output terminal of the signal gating unit. The signal to be detected is used to determine whether the touch sensing block corresponding to the signal to be detected is touched.

[0010] In one possible implementation, the signal gating unit includes: a comparison module and a gating module;

[0011] The first and second input terminals of the comparison module serve as the first and second input terminals of the signal gating unit, respectively.

[0012] The output of the comparator module is used to output a differential pressure signal; the differential pressure signal represents the difference between the first voltage signal received at the second input of the comparator module and the first voltage signal received at the first input of the comparator module.

[0013] The input terminal of the gating module is electrically connected to the output terminal of the comparator module, and the output terminal of the gating module serves as the output terminal of the signal gating unit.

[0014] The gating module is used to select the first voltage signal with the larger voltage signal as the signal to be detected and output it from the output terminal of the gating module based on the differential pressure signal.

[0015] In one possible implementation, the first and second terminals of the gating module are electrically connected to the output terminal of a charge conversion unit, the third terminal of the gating module serves as the input terminal of the gating module, and the fourth and fifth terminals of the gating module both serve as the output terminals of the gating module.

[0016] The gating module is used to turn on the second and fifth terminals of the gating module if the differential pressure signal is greater than zero, and output the first voltage signal input from the second terminal of the gating module as the signal to be detected; if the differential pressure signal is less than zero, the first and fourth terminals of the gating module are turned on, and output the first voltage signal input from the first terminal of the gating module as the signal to be detected; if the differential pressure signal is zero, the gating module does not output the signal to be detected.

[0017] In one possible implementation, the comparison module includes: a first resistor, a second resistor, a third resistor, a fourth resistor, and a subtractor;

[0018] The first end of the first resistor and the first end of the third resistor serve as the first input terminal and the second input terminal of the comparison module, respectively.

[0019] The second end of the first resistor and the second end of the second resistor are electrically connected and are also electrically connected to the first input terminal of the subtractor.

[0020] The second terminals of the third resistor and the fourth resistor are electrically connected and also electrically connected to the second input terminal of the subtractor.

[0021] The first end of the second resistor is electrically connected to the output of the subtractor, and the output of the subtractor serves as the output of the comparison module. The first end of the fourth resistor is grounded.

[0022] The resistance of the first resistor is the same as that of the second resistor, and the resistance of the third resistor is the same as that of the fourth resistor.

[0023] In one possible implementation, the gating module includes: a first switch submodule, a second switch submodule, a third switch submodule, and a fourth switch submodule;

[0024] The control terminals of the first switch submodule and the second switch submodule are electrically connected and together serve as the third terminal of the gating module;

[0025] The first and second terminals of the third switch submodule serve as the first and fourth terminals of the gating module, respectively.

[0026] The first and second terminals of the fourth switch submodule serve as the second and fifth terminals of the gating module, respectively.

[0027] The second terminal of the first switch submodule, the second terminal of the second switch submodule, the control terminal of the third switch submodule, and the control terminal of the fourth switch submodule are all electrically connected;

[0028] The first terminal of the first switch submodule and the first terminal of the second switch submodule are electrically connected to the first voltage terminal and the second voltage terminal, respectively. The first voltage terminal and the second voltage terminal are connected to the negative voltage and the positive voltage, respectively.

[0029] In one possible implementation, the charge conversion unit includes: a charge amplifier, a reset capacitor, and a reset control switch;

[0030] The first input terminal, the second input terminal, and the output terminal of the charge amplifier serve as the first input terminal, the second input terminal, and the output terminal of the charge conversion unit, respectively.

[0031] The first and second terminals of the reset capacitor are electrically connected to the first input terminal and the output terminal of the charge amplifier, respectively.

[0032] The first and second terminals of the reset control switch are electrically connected to the first input terminal and the output terminal of the charge amplifier, respectively.

[0033] The control terminal of the reset control switch is used to receive the reset control signal to control the switch to be turned on and off.

[0034] Secondly, embodiments of this application provide a driver chip, including: a signal processing unit and a touch sensing circuit as described in the first aspect;

[0035] The signal processing unit is electrically connected to the output of the signal gating unit. It is used to receive the signal to be detected and determine whether the touch sensing block corresponding to the signal to be detected is touched based on the signal to be detected.

[0036] In one possible implementation, the signal processing unit includes:

[0037] The analog-to-digital converter module, electrically connected to the output of the signal gating unit, is used to convert the signal to be detected into a digital signal;

[0038] The digital front-end module, electrically connected to the analog-to-digital converter module, is used to process digital signals to obtain processed digital signals.

[0039] The control module, electrically connected to the digital front-end module, is used to determine whether the touch sensing block corresponding to the signal to be detected is touched based on the processed digital signal.

[0040] Thirdly, embodiments of this application provide a display device, including a touch panel and a touch sensing circuit as described in the first aspect or a driver chip as described in the second aspect;

[0041] The touch panel includes multiple touch sensing blocks, which are electrically connected to the first input terminal of the charge conversion unit.

[0042] Fourthly, embodiments of this application provide a signal processing method applied to a touch sensing circuit as described in the first aspect, comprising:

[0043] Receive two first voltage signals; the two first voltage signals are output from the output terminals of the two charge conversion units respectively;

[0044] If one first voltage signal is greater than the other, the first voltage signal with the larger voltage signal is output as the signal to be detected; the signal to be detected is used to determine whether the touch sensing block corresponding to the signal to be detected is touched.

[0045] The beneficial technical effects of the technical solutions provided in this application include:

[0046] The touch sensing circuit of this embodiment includes a signal gating unit. The first and second input terminals of each signal gating unit are electrically connected to the output terminal of a charge conversion unit, meaning each signal gating unit can receive two first voltage signals. When touch is applied, the first voltage signal output by the charge conversion unit undergoes a positive change, i.e., the voltage corresponding to the first voltage signal increases. The signal gating unit outputs the first voltage signal with the larger voltage signal as the signal to be detected. This allows only the valid signal to be detected to be output, thus only needing to detect the valid signal to determine whether the touch sensing block corresponding to the signal has been touched. This achieves effective touch detection, shortens the detection time, and reduces unnecessary power consumption.

[0047] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0048] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0049] Figure 1 This is a schematic diagram of the structure of a touch sensing circuit provided in an embodiment of this application;

[0050] Figure 2 A schematic diagram of the structure of a signal gating unit of a touch sensing circuit provided in an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of the structure of a touch sensing circuit electrically connected to a touch sensing block and a signal processing unit, as provided in an embodiment of this application.

[0052] Figure 4 This is a schematic diagram of the structure of a driver chip provided in an embodiment of this application;

[0053] Figure 5 This is a schematic diagram of the structure of a signal processing unit of a driver chip provided in an embodiment of this application;

[0054] Figure 6 This is a schematic diagram of a driver chip and a touch sensing block electrically connected according to an embodiment of this application.

[0055] Figure label:

[0056] 10-Driver chip;

[0057] 110 - Touch sensing circuit;

[0058] 111-charge conversion unit;

[0059] 112 - Signal gating unit, 1121 - Comparison module, 1122 - Gating module;

[0060] 120 - Signal processing unit, 121 - Analog-to-digital conversion module, 122 - Digital front-end module, 123 - Control module. Detailed Implementation

[0061] This application is described in detail below. Examples of embodiments of this application are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. Furthermore, detailed descriptions of known technologies that are unnecessary for the features of this application are omitted. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0062] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0063] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0064] TDDI, or Touch and Display Driver Integration, is a display touch driver chip that integrates the touch chip and the display chip into a single chip. Because the touch functionality is integrated into the display driver chip, the device can be made thinner and the cost can be lower. However, the chip architecture is also more complex, and the design requirements for the touch driver and sensing circuits are more stringent.

[0065] TDDI typically employs a "time-division scanning" method, dividing a unit of time into two parts: one for touch scanning and the other for display driving. When the Panel is in the touch scanning phase, the TX block within the Panel converts the capacitance change caused by a finger touching the Panel into a voltage change via the AFE (Analog Front End) in the TDDI chip. This voltage change is then fed back to the ADC, and finally, through digital-to-analog conversion, it is fed back to the MCU for data processing, thereby determining whether the TX block is touched.

[0066] However, as panel sizes increase, the number of touch input (TX) blocks within the panel also increases, leading to a greater number of analog feeder elements (AFEs). The more analog signals fed back by the AFEs, the more signals the ADC and MCU need to process. Furthermore, since there is typically only one touch input point at a given time, only one actual, valid touch signal needs to be detected; the other analog signals fed back by the AFEs are invalid.

[0067] Since converting and detecting all touch signals is time-consuming and power-consuming, there is a need for a method to more accurately and efficiently identify valid touch signals.

[0068] The touch sensing circuit, driver chip, display device, and signal processing method provided in this application are intended to solve the above-mentioned technical problems of the prior art.

[0069] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments.

[0070] This application provides a touch sensing circuit 110, see [link to relevant documentation] Figure 1 As shown, it includes: multiple charge conversion units 111 and multiple signal gating units 112, with each pair of charge conversion units 111 corresponding to one signal gating unit 112 electrically connected.

[0071] Combination Figure 1 and Figure 3 As shown, the first input terminal and the second input terminal of each charge conversion unit 111 are used to receive the charge conversion signal and the excitation voltage signal, respectively. The output terminal of the charge conversion unit 111 is used to output the first voltage signal. The charge conversion signal is obtained based on the charge change generated by the sensing signal of the touch sensing block corresponding to the charge conversion unit 111. The first voltage signal is obtained by converting the charge conversion signal based on the excitation voltage signal.

[0072] The first input terminal and the second input terminal of each signal gating unit 112 are respectively electrically connected to the output terminal of a charge conversion unit 111.

[0073] Each signal gating unit 112 is used to receive two first voltage signals. If one first voltage signal is greater than the other first voltage signal, the first voltage signal with the larger voltage signal is used as the signal to be detected and output from the output terminal of the signal gating unit 112. The signal to be detected is used to determine whether the touch sensing block corresponding to the signal to be detected is touched.

[0074] The touch sensing circuit 110 of this embodiment is provided with a signal gating unit 112. The first input terminal and the second input terminal of each signal gating unit 112 are respectively electrically connected to the output terminal of a charge conversion unit 111. That is, each signal gating unit 112 can receive two first voltage signals. When the touch sensing block is touched, the first voltage signal output by the charge conversion unit 111 will undergo a positive change, that is, the voltage corresponding to the first voltage signal will increase. The signal gating unit 112 outputs the first voltage signal with the larger voltage signal as the signal to be detected. This allows only the valid signal to be detected to be output. Thus, only the valid signal to be detected needs to be detected to determine whether the touch sensing block corresponding to the signal to be detected has been touched, thereby achieving effective touch detection, shortening the detection time, and reducing unnecessary power consumption.

[0075] See Figure 3 As shown, Vex represents the excitation voltage signal, and Vout1 and Vout2 are the first voltage signals output from the output terminals of the two charge conversion units 111, respectively. The charge conversion unit 111 can adopt a circuit structure similar to a charge amplifier already present in touch panels. It can convert the charge conversion signal into a first voltage signal based on the excitation voltage signal Vex, which represents the touch signal. The excitation voltage signal Vex is various electrical signals input into the circuit to observe the characteristics of a circuit system; it can be a rectangular wave signal with high and low levels.

[0076] Optionally, the AFE includes a charge conversion unit 111, which converts the capacitance change of the touch sensing block into a voltage change, and can convert the charge conversion signal corresponding to the charge change generated by touch into a first voltage signal.

[0077] Specifically, the sensing signal can be a sensing biosignal, which is a signal related to the body of an organism. The biosignal can be an autonomous signal controlled subconsciously by the user, such as a finger touching the touch panel; or, the sensing signal can also be a signal generated by a touch device touching the touch panel, such as a stylus touching the touch panel.

[0078] In some embodiments, see Figure 3 As shown, the charge conversion unit 111 includes: a charge amplifier, a reset capacitor, and a reset control switch.

[0079] The first input terminal, the second input terminal, and the output terminal of the charge amplifier serve as the first input terminal, the second input terminal, and the output terminal of the charge conversion unit 111, respectively.

[0080] The first and second terminals of the reset capacitor are electrically connected to the first input terminal and the output terminal of the charge amplifier, respectively.

[0081] The first and second terminals of the reset control switch are electrically connected to the first input terminal and the output terminal of the charge amplifier, respectively.

[0082] The control terminal of the reset control switch is used to receive the reset control signal to control the switch to be turned on and off.

[0083] like Figure 3 As shown, CA represents the charge amplifier, Cfb represents the reset capacitor, RET represents the reset control signal received by the reset control switch, Cf1 and Cf2 are the capacitances generated by the finger during touch, and Cb is the base capacitance of the touch panel itself. The inverting and non-inverting inputs of the charge amplifier are the first and second inputs, respectively. The charge conversion signal is connected to the inverting input of the charge amplifier, and the non-inverting input receives the excitation voltage signal Vex. A reset capacitor and a reset control switch are connected between the inverting input and the output of the charge amplifier.

[0084] based on Figure 3 The structure of the charge conversion unit 111 shown indicates that when touch is present, the first voltage signal will have a positive voltage gain, that is, the first voltage signal will become larger. The principle is as follows:

[0085] Reset phase: RST = High, Vex = Low, Cf is the capacitance generated by the finger during touch, such as... Figure 3 The result can be Cf1 or Cf2; at this time, Qct = VexL × (Cb + Cf) and Qcfb = Vout × Cfb. Since Vout = 0, Qcfb = 0, thus resetting Cfb.

[0086] In the above formula, RST = High indicates that RST is at a high level, Vex = Low indicates that Vex is at a low level, Qct indicates the charge at the negative input terminal of CA, Qcfb indicates the charge at the output terminal of CA, Cb indicates the capacitance of capacitor Cb, Cf indicates the capacitance of capacitor Cf, Cfb indicates the capacitance of capacitor Cfb, VexL is the low level of Vex, and Vout indicates the first voltage signal output by CA.

[0087] Feedback Phase: RST = Low, Vex = High. At this point, ΔQct = ΔVex × (Cb + Cf), ΔQcfb = (VoutH - VexH) × Cfb = ΔQct, resulting in VoutH = VexH + ΔVex × (Cb + Cf) / Cfb. Therefore, when touch is present, Cf increases, and VoutH also increases, resulting in a positive change. By detecting whether there is a positive voltage gain, the presence of touch can be identified.

[0088] In the above formula, RST = Low indicates that RST is at a low level, Vex = High indicates that Vex is at a high level, ΔQct indicates the charge change at the negative input terminal of CA, ΔVex indicates the difference between Vex being at a high level and a low level, ΔQcfb indicates the charge change at the output terminal of CA, and VoutH indicates the first voltage signal output by CA when touch is present.

[0089] Optionally, the excitation voltage signal Vex is also called the guard signal, which can effectively eliminate the negative impact of capacitor Cb on the size of the touch capacitor.

[0090] Optionally, the signal gating unit 112 can receive two first voltage signals and select the output signal with the larger voltage signal from the two first voltage signals. For example... Figure 3 As shown, the signal gating unit 112 can receive the first voltage signals Vout1 and Vout2, and select the output with the larger voltage from Vout1 and Vout2. The signal to be detected is one of Vout1 and Vout2.

[0091] Optionally, the signal gating unit 112 can be a comparison and self-connection circuit that automatically outputs the signal to be detected.

[0092] In some embodiments, see Figure 2 As shown, the signal gating unit 112 includes a comparison module 1121 and a gating module 1122.

[0093] The first and second input terminals of the comparison module 1121 serve as the first and second input terminals of the signal gating unit 112, respectively.

[0094] The output terminal of the comparison module 1121 is used to output a differential pressure signal; the differential pressure signal represents the difference between the first voltage signal received at the second input terminal of the comparison module 1121 and the first voltage signal received at the first input terminal of the comparison module 1121.

[0095] The input terminal of the gating module 1122 is electrically connected to the output terminal of the comparison module 1121, and the output terminal of the gating module 1122 serves as the output terminal of the signal gating unit 112.

[0096] The gating module 1122 is used to output the first voltage signal with a larger voltage signal as the signal to be detected from the output terminal of the gating module 1122 based on the differential pressure signal.

[0097] As an example, see Figure 3 As shown, Vout3 represents the differential pressure signal, and Vout3 is the difference between Vout2 and Vout1. The gating module 1122 can determine the signal to be detected output by the gating module 1122 based on whether the differential pressure signal is positive or negative.

[0098] In practical applications, the differential pressure signal can also be based on comparing two first voltage signals, outputting high-level and low-level signals. This allows the gating module 1122 to implement different conduction paths based on the high-level and low-level signals, thereby outputting the first voltage signal with the larger voltage signal. Similarly, the differential pressure signal can also be preset indication information. Based on the indication information, the gating module 1122 determines and outputs the first voltage signal with the larger voltage signal.

[0099] In some embodiments, see Figure 3 As shown, the comparison module 1121 includes: a first resistor, a second resistor, a third resistor, a fourth resistor, and a subtractor.

[0100] The first end of the first resistor and the first end of the third resistor serve as the first input terminal and the second input terminal of the comparison module 1121, respectively.

[0101] The second end of the first resistor and the second end of the second resistor are electrically connected and are also electrically connected to the first input terminal of the subtractor.

[0102] The second terminals of the third resistor and the fourth resistor are electrically connected and are also electrically connected to the second input terminal of the subtractor.

[0103] The first end of the second resistor is electrically connected to the output of the subtractor, and the output of the subtractor serves as the output of the comparator module 1121. The first end of the fourth resistor is grounded.

[0104] The resistance of the first resistor is the same as that of the second resistor, and the resistance of the third resistor is the same as that of the fourth resistor.

[0105] like Figure 3 As shown, R1, R2, R3, and R4 represent the first, second, third, and fourth resistors, respectively. The voltages at the first and second input terminals of the subtractor are the same. The negative and positive input terminals of the subtractor serve as the first and second input terminals, respectively.

[0106] Specifically, see Figure 3 As shown, the principle by which the comparison module 1121 compares the magnitudes of electrical signals is as follows:

[0107] Based on the working principle of the charge conversion unit 111, when a touch occurs, Cf increases and VoutH also increases. By detecting whether there is a positive voltage gain in VoutH, the presence of touch can be identified. The voltage output by the first charge amplifier CA is Vout1, and the voltage output by the second charge amplifier CA is Vout2. At this time, the two are compared by a subtractor.

[0108] Based on the principle of virtual open circuit, the current through resistor R3 is equal to the current through resistor R4. Similarly, the current through resistor R2 is equal to the current through resistor R1. Therefore, we have (Vout2–V+) / R3=V+ / R4 and (Vout1–V-) / R1=(V--Vout3) / R2.

[0109] In the above formula, V- and V+ are the voltages at the first and second input terminals of the subtractor, respectively, and R1, R2, R3, and R4 are the resistance values ​​of resistor R1, resistor R2, resistor R3, and resistor R4, respectively.

[0110] Assuming R3 = R4, then V+ = Vout2 / 2; assuming R1 = R2, then V- = (Vout3 + Vout1) / 2;

[0111] Since V+ = V-, Vout3 = Vout2 - Vout1. The differential voltage signal Vout3 output by the comparison module 1121 can reflect the magnitudes of the first voltage signals Vout2 and Vout1.

[0112] In some embodiments, see Figure 3 As shown, the first and second ends of the gating module 1122 are electrically connected to the output end of a charge conversion unit 111, respectively. The third end of the gating module 1122 serves as the input end of the gating module 1122, and the fourth and fifth ends of the gating module 1122 both serve as the output ends of the gating module 1122.

[0113] The gating module 1122 is used to turn on its second and fifth terminals when the differential pressure signal is greater than zero, and output the first voltage signal input from the second terminal of the gating module 1122 as the signal to be detected; when the differential pressure signal is less than zero, the gating module 1122 turns on its first and fourth terminals, and outputs the first voltage signal input from the first terminal of the gating module 1122 as the signal to be detected; when the differential pressure signal is zero, the gating module 1122 does not output the signal to be detected.

[0114] Optionally, the gating module 1122 is a self-connecting circuit that can realize different conduction paths based on the different received differential voltage signals, and output the first voltage signal with the larger voltage signal as the signal to be detected.

[0115] In some embodiments, the gating module 1122 includes: a first switch submodule, a second switch submodule, a third switch submodule, and a fourth switch submodule.

[0116] The control terminals of the first switch submodule and the second switch submodule are electrically connected and together serve as the third terminal of the gating module 1122.

[0117] The first and second terminals of the third switch submodule serve as the first and fourth terminals of the gating module 1122, respectively.

[0118] The first and second terminals of the fourth switch submodule serve as the second and fifth terminals of the gating module 1122, respectively.

[0119] The second terminal of the first switch submodule, the second terminal of the second switch submodule, the control terminal of the third switch submodule, and the control terminal of the fourth switch submodule are all electrically connected.

[0120] The first terminal of the first switch submodule and the first terminal of the second switch submodule are electrically connected to the first voltage terminal and the second voltage terminal, respectively. The first voltage terminal and the second voltage terminal are connected to the negative voltage and the positive voltage, respectively.

[0121] See Figure 3 As shown, the first switch submodule includes switch device T1, the second switch submodule includes switch device T2, the third switch submodule includes switch device T3, and the fourth switch submodule includes switch device T4. The first, second, and control terminals of switch device T1 serve as the first, second, and control terminals of the first switch submodule, respectively; the first, second, and control terminals of switch device T2 serve as the first, second, and control terminals of the second switch submodule, respectively; the first, second, and control terminals of switch device T3 serve as the first, second, and control terminals of the third switch submodule, respectively; and the first, second, and control terminals of switch device T4 serve as the first, second, and control terminals of the fourth switch submodule, respectively. The voltages of the first and second voltage terminals are V1 and V2, respectively.

[0122] Optionally, switching devices T1 and T3 can be PMOS, and switching devices T2 and T4 can be NMOS. The source and drain of each switching device are set according to the actual circuit structure, and the gate of each switching device is used as the control terminal.

[0123] See Figure 3As shown, when neither of the touch sensing blocks corresponding to the two charge conversion units 111 is touched, Vout2 = Vout1, Vout3 = 0. At this time, switching devices T1 and T2 are both turned off, as are switching devices T3 and T4. Therefore, the connection between the two charge conversion units 111 and the subsequent signal processing unit 120 is broken, and the signal processing unit 120 does not need to process the signals fed back by the charge conversion units 111.

[0124] When the touch sensing block corresponding to the first charge conversion unit 111 is touched, Vout1 > Vout2, Vout3 < 0. At this time, switch T1 is turned on, switch T2 is turned off, switch T3 is turned on, and switch T4 is turned off. Therefore, the first charge conversion unit 111 is connected to the signal processing unit 120 through the signal gating unit 112 and turned on. The second charge conversion unit 111 is disconnected from the signal processing unit 120. At this time, the signal processing unit 120 does not need to process the signal fed back by the second charge conversion unit 111, but only needs to process the signal fed back by the first charge conversion unit 111.

[0125] When the touch sensing block corresponding to the second charge conversion unit 111 is touched, Vout2 > Vout1, Vout3 > 0. At this time, switch T2 is turned on, switch T1 is turned off, switch T4 is turned on, and switch T3 is turned off. Therefore, the second charge conversion unit 111 is connected to the signal processing unit 120 through the signal gating unit 112 and turned on. The first charge conversion unit 111 is disconnected from the signal processing unit 120. At this time, the signal processing unit 120 does not need to process the signal fed back by the first charge conversion unit 111, but only needs to process the signal fed back by the second charge conversion unit 111.

[0126] By using the above method, the invalid first voltage signal can be disconnected while accurately identifying the valid first voltage signal, thereby reducing unnecessary power consumption loss caused by the signal processing unit 120 and other components when processing invalid data.

[0127] Based on the same inventive concept, this application provides a driver chip, see [link to relevant documentation]. Figure 4 As shown, the driver chip 10 includes a signal processing unit 120 and a touch sensing circuit 110 according to any embodiment of this application.

[0128] The signal processing unit 120 is electrically connected to the output terminal of the signal gating unit 112. The signal processing unit 120 is used to receive the signal to be detected and determine whether the touch sensing block corresponding to the signal to be detected is touched based on the signal to be detected.

[0129] Combination Figure 3 and Figure 4As shown, the fourth and fifth terminals of the gating module 1122 are both electrically connected to the signal processing unit 120. The second terminals of the third and fourth switch submodules are connected to the signal processing unit 120, allowing Vout1 or Vout2 to be output to the signal processing unit 120 for signal processing.

[0130] In some embodiments, see Figure 5 As shown, the signal processing unit 120 includes: an analog-to-digital conversion module 121, a digital front-end module 122, and a control module 123.

[0131] The analog-to-digital converter module 121 is electrically connected to the output terminal of the signal gating unit 112. The analog-to-digital converter module 121 is used to convert the signal to be detected into a digital signal.

[0132] The digital front-end module 122 is electrically connected to the analog-to-digital converter module 121. The digital front-end module 122 is used to set and process the digital signal to obtain the processed digital signal.

[0133] The control module 123 is electrically connected to the digital front-end module 122. The control module 123 is used to determine whether the touch sensing block corresponding to the signal to be detected is touched based on the processed digital signal.

[0134] Optionally, the digital front-end module 122 mainly preprocesses the digital signal, including filtering and other preprocessing steps. After receiving the processed digital signal, the control module 123 performs predetermined calculations, such as comparing the processed digital signal with a preset value. If the processed digital signal equals the preset value, it is determined that the touch sensor corresponding to the signal to be detected is touched; or, if the processed digital signal is within a preset range, it is determined that the touch sensor corresponding to the signal to be detected is touched. The preset range is set based on the processed digital signal when the touch sensor is touched in actual application. It is conceivable that those skilled in the art can also use other possible methods to determine whether the touch sensor corresponding to the signal to be detected is touched based on the processed digital signal.

[0135] In order to accurately identify the valid first voltage signal and reduce unnecessary power consumption losses from the signal processing unit 120 and other units processing invalid data, the driver chip 10 of this application introduces a signal gating unit 112 between the charge conversion unit 111 and the signal processing unit 120 to filter the touch sensing signal, i.e., the first voltage signal. During the non-touch phase, the signal gating unit 112 remains off to avoid detecting invalid signals. During the touch detection phase, the signal gating unit 112 compares the magnitudes of the first electrical signals output by the two charge conversion units 111. The first voltage signal with a positive voltage gain is transmitted to the signal processing unit 120 as the detection signal, while the charge conversion unit 111, which has no voltage change, remains disconnected from the signal processing unit 120. This reduces the signal processing load of the signal processing unit 120, thereby achieving effective touch detection and reducing unnecessary power consumption losses.

[0136] Based on the same inventive concept, embodiments of this application provide a display device, including a touch panel, and a touch sensing circuit 110 or a driver chip 10 of any embodiment of this application.

[0137] The touch panel includes multiple touch sensing blocks, which are electrically connected to the first input terminal of the charge conversion unit 111.

[0138] As an example, see Figure 6 The diagram shows a schematic of a driver chip electrically connected to a touch sensing block, where the touch sensing circuit 110 of this application is applied to a TDDI chip. Figure 6 As shown, TX blocks represent touch sensing blocks, and multiple TX blocks are arranged in an array. The driver chip 10 includes two multiplexers (MUX), namely Left MUX and Right MUX. Multiple TX blocks located on the left side of the touch panel are electrically connected to Left MUX, and multiple TX blocks located on the right side of the touch panel are electrically connected to Right MUX. Each AFE includes a charge conversion unit 111. If a column of TX blocks has N TX blocks, then Left MUX is electrically connected to N charge conversion units 111 in sequence, and Right MUX is electrically connected to N charge conversion units 111 in sequence. Left MUX and Right MUX sequentially control the charge conversion units 111 of each column of TX blocks to be electrically connected to the corresponding AFEs.

[0139] Taking Left MUX as an example, when Left MUX selects the first column TX block, each charge conversion unit 111 collects the data of the first column and converts it into a first voltage signal. When Left MUX selects the second column TX block, each charge conversion unit 111 collects the data of the second column and converts it into a first voltage signal.

[0140] See Figure 6 As shown, the analog-to-digital conversion module 121 includes two analog-to-digital converters (ADCs). One ADC is electrically connected to a charge conversion unit 111 electrically connected to the Left MUX, and the other ADC is electrically connected to a charge conversion unit 111 electrically connected to the Right MUX. The digital front-end module 122 includes two digital front-ends (DFEs), each DFE being electrically connected to one ADC. The control module 123 includes a microcontroller unit (MCU).

[0141] When the Panel is in the touch scanning stage, the TX block set in the Panel can convert the capacitance change caused by the finger touching the Panel into a voltage change through the charge conversion unit 111 of the AFE in the TDDI chip under the control of the multiplexer MUX, and then feed it back to the ADC. Finally, it feeds it back to the DFE and MCU for data processing through digital-to-analog conversion, so as to determine whether there is a touch at the position of the TX block.

[0142] The display device of this application embodiment includes a driver chip 10. The driver chip 10 can filter touch sensing signals, i.e., filter the first voltage signal, by introducing a signal gating unit 112 between the charge conversion unit 111 and the signal processing unit 120. During the non-touch phase, the signal gating unit 112 remains off to avoid invalid signal detection. During the touch detection phase, the signal gating unit 112 compares the magnitudes of the first electrical signals output by the two charge conversion units 111. The first voltage signal with positive voltage gain is transmitted to the signal processing unit 120 as the signal to be detected, while the charge conversion unit 111 without voltage change remains disconnected from the signal processing unit 120. This reduces the signal processing load of the signal processing unit 120, thereby achieving effective touch detection and reducing unnecessary power consumption.

[0143] Based on the same inventive concept, embodiments of this application provide a signal processing method applied to the touch sensing circuit 110 in any embodiment of this application, including:

[0144] Two first voltage signals are received; the two first voltage signals are output from the output terminals of the two charge conversion units 111 respectively;

[0145] If one first voltage signal is greater than the other, the first voltage signal with the larger voltage signal is output as the signal to be detected; the signal to be detected is used to determine whether the touch sensing block corresponding to the signal to be detected is touched.

[0146] Optionally, the signal processing method in this embodiment is executed by a signal gating unit 112. The signal gating unit 112 includes a comparison module 1121 and a gating module 1122.

[0147] Optionally, combined Figure 3 As shown, if one first voltage signal is greater than the other, the first voltage signal with the larger voltage signal is output as the signal to be detected. This includes: if the voltage difference signal output by the comparison module 1121 is greater than zero, the second and fifth terminals of the gating module 1122 are turned on, and the first voltage signal input from the second terminal of the gating module 1122 is output as the signal to be detected; if the voltage difference signal output by the comparison module 1121 is less than zero, the first and fourth terminals of the gating module 1122 are turned on, and the first voltage signal input from the first terminal of the gating module 1122 is output as the signal to be detected.

[0148] Optionally, the signal processing method in this application embodiment further includes: if the differential pressure signal output by the comparison module 1121 is zero, then the gating module 1122 does not output the signal to be detected.

[0149] The signal processing method provided in this application is applied to the touch sensing circuit 110 of any embodiment of this application. It has the same inventive concept and the same beneficial effects as the touch sensing circuit 110 of the previous embodiments. For the contents not shown in detail in this signal processing method, please refer to the touch sensing circuit 110 of the previous embodiments, which will not be repeated here.

[0150] Those skilled in the art will understand that the steps, measures, and solutions in the various operations, methods, and processes discussed in this application can be alternated, modified, combined, or deleted. Furthermore, other steps, measures, and solutions in the various operations, methods, and processes discussed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted. Furthermore, steps, measures, and solutions in the prior art that are similar to those disclosed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0151] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0152] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0153] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0154] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A touch sensing circuit, comprising: The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method.

2. The touch sensing circuit of claim 1, wherein, The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method.

3. The touch sensing circuit of claim 2, wherein, The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method.

4. The touch sensing circuit of claim 2, wherein, The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to a touch control system and a touch control method. The application relates to A first end of the second resistor is electrically connected with an output end of the subtractor, the output end of the subtractor serving as an output end of the comparison module, and a first end of the fourth resistor is grounded. The first resistor has the same resistance as the second resistor, and the third resistor has the same resistance as the fourth resistor.

5. The touch sensing circuit of claim 3, wherein, The gating module comprises a first switch sub-module, a second switch sub-module, a third switch sub-module and a fourth switch sub-module. Control ends of the first switch sub-module and the second switch sub-module are electrically connected and serve as a third end of the gating module. First and second ends of the third switch sub-module serve as a first and fourth end of the gating module, respectively. First and second ends of the fourth switch sub-module serve as a second and fifth end of the gating module, respectively. Second ends of the first and second switch sub-modules, a control end of the third switch sub-module and a control end of the fourth switch sub-module are electrically connected. First ends of the first and second switch sub-modules are electrically connected with first and second voltage ends, respectively, and the first and second voltage ends are connected with negative and positive voltages, respectively.

6. The touch sensing circuit of claim 1, wherein, The charge conversion unit comprises a charge amplifier, a reset capacitor and a reset control switch. First and second input ends and an output end of the charge amplifier serve as first and second input ends and an output end of the charge conversion unit, respectively. First and second ends of the reset capacitor are electrically connected with the first input end of the charge amplifier and the output end of the charge amplifier, respectively. First and second ends of the reset control switch are electrically connected with the first input end of the charge amplifier and the output end of the charge amplifier, respectively. A control end of the reset control switch is configured to receive a reset control signal to control conduction and disconnection of the reset control switch.

7. A driving chip, characterized by comprising: The display device comprises a touch panel and the touch sensing circuit or the driving chip. The touch panel comprises a plurality of touch sensing blocks, and the touch sensing blocks are electrically connected with the first input end of the charge conversion unit. The display device comprises a touch panel and the touch sensing circuit or the driving chip.

8. The driving chip according to claim 7, characterized in that, The touch panel comprises a plurality of touch sensing blocks, and the touch sensing blocks are electrically connected with the first input end of the charge conversion unit. ​ ​ ​ ​ ​ 10. A signal processing method applied to the touch sensing circuit according to any one of claims 1-6, characterized in that, ​ receive two first voltage signals; the two first voltage signals correspond to outputs from two charge conversion units; if one of the first voltage signals is greater than the other first voltage signal, output the first voltage signal with the greater voltage as a to-be-detected signal; the to-be-detected signal is used to determine whether a touch sensing block corresponding to the to-be-detected signal exists touch.

Images